Shellfish, such as crab, shrimp, lobster and the like have a number of unique characteristics. Shellfish meat has a characteristic taste and texture. Shellfish are typically cooked in a manner different than that of other meat or fish products. Shellfish tend to spoil relatively quickly in storage due to the usual presence of spoilage bacteria, such as Listeria monocytogenes. In addition, such microorganisms as infectious Staphylococcus, Salmonella and other potentially pathogenic microorganisms are frequently present.
There have been attempts to improve the storage life of shellfish which have resulted in various degrees of failure. Although freezing deters spoilage, freezing also results in deterioration of shellfish texture and taste. Shellfish meat removed from the shell may be effectively pasteurized, but such method has not been usable on meat in the shell because when done in water, the meat becomes saturated and when done in air, the meat is cooked. Saturated shellfish meat loses both taste and texture due to cell rupture or degradation. Cooking is not desired in this process because the consumer usually wishes to purchase a fresh, uncooked product, or, if the shellfish product is to be purchased after cooking, pasteurization causes overcooking of the already cooked shellfish.
Because of the ineffectiveness of prior attempts to extend shellfish shelf-life known in the industry, the acceptable shelf-life of shellfish in the shell under refrigeration is a maximum of 7-10 days. Storage of shellfish without refrigeration has not been possible. This means that a restaurant or retail store which sells shellfish must obtain fresh supplies of shellfish at least weekly, and must dispose of the older product.
The short shelf-life of in-the-shell shellfish products also requires the consumer to be wary of the possibility of purchasing a shellfish product that is at or near its expiration time and, if the shellfish product is purchased in good time, to use the shellfish fairly quickly. The shelf-life problem is substantially similar whether the shellfish are fresh or cooked.
As used herein, the terms "shellfish" and "shellfish product" are used interchangeably and refer to either the entire shellfish or to the shellfish meat portions removed from the shell.
Therefore, an objective of the invention is to provide a process for extending the shelf-life of shellfish.
An additional objective of the invention is to provide a process which retains the natural flavor and texture of a shellfish product.
A further objective of the invention is to provide a process which is effective with either fresh or cooked shellfish.
These and other objectives of the invention disclosed will become apparent to those skilled in the art as the description below is understood.